TWI490009B - Particle beam irradiation device - Google Patents

Description

Particle beam irradiation device

The present application claims priority based on Japanese Patent Application No. 2012-023127, filed on Feb. 6, 2012. The entire contents of the application are hereby incorporated by reference.

The present invention relates to a particle beam irradiation apparatus that irradiates an object to be irradiated with particle rays.

Conventionally, for example, a device described in Patent Document 1 is known as a particle beam irradiation device that is used for radiation treatment of a tumor or the like. The particle beam irradiation apparatus includes: a scanning means (electromagnet) for scanning a particle beam; a current supply means (power source) for supplying a current to the scanning means; and a scanning control means (a command value transmitting unit) for transmitting to the current supply means The current command value controls the scanning of the particle ray by the scanning means. In the particle beam irradiation apparatus, the scanning control means transmits a current command value to the current supply means in accordance with the treatment plan planned in advance, thereby changing the current supply to the scanning means by the current supply means, and performing scanning of the particle beam according to the treatment plan. control.

[Previous Technical Literature] [Patent Literature]

Japanese Laid-Open Patent Publication No. 2006-288875

However, in particle beam therapy, if there is a deviation between the scanning of the particle beam in the prior treatment plan and the scanning of the actual particle beam, the amount of the irradiation line may be excessive or insufficient due to the site of the tumor, resulting in insufficient supply. Problems such as treatment effects. Therefore, it is strongly demanded to improve the accuracy of the scanning control of the particle beam of the particle beam irradiation apparatus.

Accordingly, it is an object of the present invention to provide a particle beam irradiation apparatus capable of performing scanning control of particle ray with high precision.

As a result of intensive research by the inventors, it has been found that the scanning control means transmits a current command value to the current supply means, and then there is a deviation from the current supply means to the delay time until the scanning means for supplying the current actually scans the particle beam. This deviation of the delay time is one of the reasons for the decrease in the accuracy of the scanning control.

As a result of further research by the inventors, it was found that the deviation of the delay time is caused by the difference between the operation timing of the scanning control means and the operation timing of the current supply means. That is, it is ascertained that the operation timing of the scanning control means and the operation timing of the current supply means are obtained within a delay time from when the scanning control means transmits the current command value to when the scanning means actually scans the particle beam. The deviation caused by the difference is the cause of the deviation of the entire delay time.

Fig. 5 is a diagram for explaining the deviation of the timing delay time. In Fig. 5, the transmission timing of the current command value at the transmission end operation timing is shown as s0 to s2. Further, the reception timing of the current command value at the receiving end operation timing is set to r0 to r2. As shown in FIG. 5, when the period of the transmission end operation timing is different from the period of the reception end operation timing, the transmission timing of the current command value by the scan control means and the reception timing of the current command value by the current supply means There is a delay between the deviations.

Therefore, in one aspect of the invention, a particle beam irradiation apparatus for irradiating a particle beam with an object to be irradiated includes: a scanning means for scanning a particle beam; a current supply means for supplying a current to the scanning means; and a scanning control means The scanning of the particle beam by the scanning means is controlled by transmitting a current command value to the current supply means, and the operation timing period of the scanning control means is equal to the period of the operation timing of the current supply means.

According to the particle beam irradiation apparatus of the present invention, since the period of the operation timing of the scanning control means is equal to the period of the operation timing of the current supply means, the delay time of the operation clock of the scanning control means and the current supply means can be made constant, and can be avoided. A deviation of the delay time until the scanning means actually scans the particle beam after the scanning control means transmits the current command value. Therefore, according to the above-described particle beam irradiation apparatus, it is possible to avoid the delay of the delay time, such as at a certain irradiation position, the particle beam irradiation is longer than the treatment plan, and at other irradiation positions, the particle beam irradiation is more than the treatment plan. The situation in a shorter time. Therefore, according to the above-described particle beam irradiation apparatus, it is possible to precisely control each irradiation according to the treatment plan. Scanning control of particle ray with high precision of illumination time in position.

The particle beam irradiation apparatus may be configured such that the scanning control means has a transmitting unit that transmits an operation timing signal to the current supply means, and the current supply means has a receiving unit that receives the operation timing signal transmitted by the transmitting unit.

According to the particle beam irradiation apparatus, the operation timing signal is transmitted from the transmission unit of the scan control means to the reception unit of the current supply means, and the current supply means can be driven at the operation timing of the cycle equal to the operation timing of the scan control means. Therefore, in the particle beam irradiation apparatus described above, since it is not necessary to separately provide an operation timing signal transmitting unit for matching the operation timing of the scanning means and the operation timing of the current supply means, the device configuration can be simplified.

Further, the particle beam irradiation apparatus further includes a position measuring means for measuring the position of the particle beam scanned by the scanning means, and the scanning control means may be based on the planned position of the particle beam corresponding to the current command value and the position measuring means. The result of the comparison of the measured positions of the measured particle rays determines whether or not there is an abnormality in the scanning of the particle beam.

According to the particle beam irradiation apparatus described above, since the delay time can be made substantially constant by suppressing the variation in the delay time, the influence of the delay time on the position of the particle beam can be calculated and the particle beam can be accurately compared. Position and actual measurement position. Therefore, according to the particle beam irradiation apparatus described above, it is possible to accurately determine whether or not there is an abnormality in the scanning control of the particle beam based on the comparison result of the planned position of the particle beam and the measurement position.

According to the present invention, scanning control of high-precision particle rays can be performed.

1‧‧‧Electrical particle beam therapy device (particle beam irradiation device)

2‧‧‧Accelerator

3‧‧‧ transmission line

4‧‧‧ Department of Irradiation

5‧‧‧Location measurement monitor (location measurement method)

6‧‧‧Scan electromagnet (scanning means)

7‧‧‧Scanner power supply (current supply means)

8‧‧‧Treatment Planning Department

9‧‧‧Lighting Control Department

10‧‧‧Scan controller (scanning control means)

11‧‧‧ Beam Control Department

12‧‧‧Delivery Department

13A, 13B‧‧‧ Receiving Department

50‧‧‧ patients

51‧‧‧Tumor (irradiated body)

100‧‧‧ treatment table

A‧‧‧ Direction

L‧‧‧ scan pattern

R‧‧‧ charged particle beam

Fig. 1 is a view showing an embodiment of a particle beam irradiation apparatus according to the present invention.

Fig. 2 is a view for explaining scanning irradiation by particle beam.

Figure 3 is a diagram for explaining the signal sent by the scan controller to the scanner power supply.

Fig. 4 is a view showing the operation timing of the scan controller and the operation timing of the scanner power supply.

Fig. 5 is a diagram for explaining the deviation of the timing delay time.

Hereinafter, a preferred embodiment of the particle beam irradiation apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in Fig. 1 and Fig. 2, the charged particle beam therapy apparatus (particle beam irradiation apparatus) 1 of the present embodiment irradiates a tumor (irradiated body) 51 of a patient 50 on the treatment table 100 with a charged particle beam R. For radiation therapy. Examples of the charged particle beam R include a proton line or a heavy particle (heavy ion) line.

The charged particle beam therapy apparatus 1 performs continuous irradiation or intermittent irradiation of the charged particle beam R by the scanning method. Specifically, charged particles In the sub-radiation treatment apparatus 1, the tumor 51 is assumed to be divided into a plurality of layers in the depth direction, and continuous irradiation (raster scanning or linear scanning) is performed while scanning the charged particle beam R along the scanning pattern L set in each layer. Or intermittent illumination (dot scan).

The charged particle beam therapy apparatus 1 includes an accelerator 2 that accelerates charged particles to emit charged particle rays R, a transmission line 3 that transmits charged particle beams R emitted from the accelerator 2, and an irradiation unit 4 that irradiates the patient's tumor by the transmission line 3. The charged particle beam R to be transmitted; the position measuring monitor (position measuring means) 5 for measuring the irradiation position of the charged particle beam R irradiated from the irradiation unit 4.

The accelerator 2 emits the charged particle beam R by accelerating the charged particles. As the accelerator 2, for example, a cyclotron, a synchrotron, a synchrocyclotron, or a linear accelerator can be used.

The charged particle beam R emitted from the accelerator 2 is transmitted to the irradiation unit 4 via the transmission line 3. The advancing direction of the charged particle beam R transmitted from the transmission line 3 into the illuminating unit 4 is indicated by an arrow A.

The illuminating unit 4 irradiates the tumor 51 in the body of the patient 50 on the treatment table 100 with the charged particle beam R. The illuminating unit 4 includes a scanning electromagnet (scanning means) 6 for scanning the charged particle beam R. In the scanning electromagnet 6, the scanning of the charged particle beam R is performed by the change of the magnetic field. The scanning electromagnet 6 has a first scanning electromagnet 6A that scans the charged particle beam R in the X direction perpendicular to the direction A; and the second scanning electromagnet 6B in the Y direction with respect to the direction A and the direction perpendicular to the X direction. The charged particle beam R is scanned up.

The scanning electromagnet 6 supplies a current from a scanner power source (current supply means) 7 disposed outside the irradiation unit 4. The scanner power supply 7 changes the current supplied to the scanning electromagnet 6 in accordance with the current command value from the scan controller 10 to be described later. The scanner power supply 7 has a first power supply (X power supply) 7A, and supplies a current to the first scanning electromagnet 6A, and a second power supply (Y power supply) 7B supplies a current to the second scanning electromagnet 6B.

The position measuring monitor 5 measures the irradiation position of the charged particle beam R scanned by the scanning electromagnet 6 (the position in the XY plane perpendicular to the direction A of the charged particle beam R). The position measuring monitor 5 includes a lattice-shaped wire grid composed of a plurality of metal wires extending in the X direction or the Y direction, and detects that the charged particle beam R is in contact with the wire grid. The generated charge is used to measure the irradiation position of the charged particle beam R.

Next, the irradiation control of the charged particle beam R of the charged particle beam therapy apparatus 1 will be described. The charged particle beam therapy system 1 includes a treatment planning unit 8, an irradiation control unit 9, a scan controller (scanning control means) 10, and a light beam control unit 11.

In the treatment planning section 8, a treatment plan for treating the tumor 51 of the patient 50 is established. The treatment planning unit 8 formulates a treatment plan based on various materials that have been input. The treatment plan includes a scanning pattern L of the charged particle beam R corresponding to each layer in which the tumor 51 is assumed to be divided into a plurality of layers in the depth direction. The scanning position information of the charged particle beam R per predetermined time is included in the scanning pattern L.

The irradiation control unit 9 is a treatment plan based on the treatment planning unit 8. To control the irradiation of the charged particle beam R. The irradiation control unit 9 transmits information related to the treatment plan acquired from the treatment planning unit 8 to the scan controller 10.

Further, the illumination control unit 9 transmits an emission preparation signal to the beam controller 11 in accordance with the request signal from the scan controller 10. When the beam controller 11 receives the emission preparation signal, the accelerator 2 is controlled to start preparation for emission of the charged particle beam R. When the preparation for emission of the charged particle beam R is completed, the beam controller 11 transmits a signal indicating that the emission preparation is completed to the irradiation control unit 9 and the scanning controller 10.

As shown in FIGS. 1 and 3, the scan controller 10 performs scanning control of the charged particle beam R based on the information of the treatment plan transmitted from the irradiation control unit 9. The scan controller 10 transmits a current command value corresponding to the treatment plan to the scanner power source 7. The scan controller 10 changes the supply of current from the scanner power supply 7 to the scanning electromagnet 6 by the current command value, thereby indirectly controlling the scanning of the charged particle beam R by the scanning electromagnet 6.

The scan controller 10 transmits a first current command value (X current command value) for scanning the charged particle beam R in the X direction to the first power source 7A. Similarly, the scan controller 10 transmits a second current command value (Y current command value) for scanning the charged particle beam R in the Y direction to the second power source 7B.

Further, the scan controller 10 drives the internal basic timing as an operation timing. The scan controller 10 has a signaling unit 12 that transmits its own operational timing signal to the scanner power supply 7. The signaling unit 12 is for making The operation timing cycle of the scanner power supply 7 is equal to the operation timing cycle of the scan controller 10, and the operation timing signal is transmitted to the scanner power supply 7.

On the other hand, the X power source 7A and the Y power source 7B of the scanner power supply 7 have receiving sections 13A and 13B that respectively receive operation timing signals. In the X power source 7A and the Y power source 7B, the receiving unit 13A, 13B receives the operation timing signal transmitted from the transmitting unit 12, and performs the scanning electromagnet 6 at the operation timing of the cycle equal to the operation timing of the scan controller 10. The supply of current. Specifically, the operation timing of the operation timing signals received by the receiving units 13A and 13B is used as the operation timing of the X power source 7A and the Y power source 7B. Alternatively, the operation timings of the X power source 7A and the Y power source 7B are synchronized with the operation timings of the operation timing signals received by the receiving units 13A and 13B. In addition, the period is equal to the same period, and the period is strictly the same, and an error of 10 μs or less is allowed.

Further, the scanning controller 10 acquires information on the measurement position of the charged particle beam R by the position measuring monitor 5. The scanning controller 10 performs a planned position of the charged particle beam R corresponding to the treatment plan (a planned position of the charged particle beam R corresponding to the current command value) and a measurement position of the charged particle beam R acquired by the position measuring monitor 5. Comparison.

The scan controller 10 determines whether or not there is an abnormality in the scanning control of the charged particle beam R based on the comparison result between the planned position of the charged particle beam R and the measurement position. Specifically, the scan controller 10 determines whether or not there is an abnormality in the scan control by determining whether or not the difference between the measurement position of the charged particle beam R and the planned position of the charged particle beam R is within the allowable range.

When the scan controller 10 determines that there is an abnormality in the scan control, The irradiation stop signal is sent to the light beam control unit 11 to stop the irradiation of the charged particle beam R.

According to the charged particle beam therapy system 1 of the present embodiment described above, since the period of the operation timing of the scan controller 10 is equal to the period of the operation timing of the scanner power supply 7, the delay caused by the difference in the operation timing is not generated. The deviation of the time enables the delay time until the scan means actually scans the particle beam after the scan controller 10 transmits the current command value.

Here, FIG. 4 is a view showing an operation sequence of the scan controller 10 and an operation timing of the scanner power supply 7. In Fig. 4, the transmission timing of the current command value of the operation timing of the scan controller 10 is indicated as s0 to s2. Further, the reception timing of the current command value of the operation timing of the scanner power supply 7 is indicated as r0 to r2. Further, the delay time between the transmission timing s0 and the reception timing r0 is denoted as t0, the delay time between the transmission timing s1 and the reception timing r1 is denoted as t1, and the delay time between the transmission timing s2 and the reception timing r2 is indicated For t2.

As shown in FIG. 4, in the charged particle beam therapy system 1 of the present embodiment, since the cycle of the operation timing of the scan controller 10 is equal to the cycle of the operation timing of the scanner power supply 7, the scan controller 10 and the scan controller 10 can be When the delay time t0 to t2 of the operation timing of the scanner power supply 7 is constant, it is possible to prevent the delay time until the scanning electromagnet 6 actually scans the particle beam after the scan controller 10 transmits the current command value. Therefore, according to the charged particle beam therapy apparatus 1, it is possible to avoid the particle beam irradiation treatment at a certain irradiation position caused by the deviation of the delay time. The treatment is planned for a longer period of time, and at another illumination location, the particle beam is irradiated for a shorter period of time than the treatment plan. Therefore, according to the charged particle beam therapy apparatus 1, it is possible to perform scanning control of particle ray with high precision for accurately controlling the irradiation time at each irradiation position in accordance with the treatment plan.

Further, in the charged particle beam therapy system 1, the operation timing signal is transmitted from the scan controller 10 to the scanner power supply 7 to drive the scanner power supply 7 at an operation timing of a cycle equal to the operation timing of the scan controller 10. Therefore, according to the charged particle beam therapy system 1, since it is not necessary to separately provide an operation timing signal transmitting unit for matching the operation timing of the scan controller 10 and the cycle of the operation timing of the scanner power supply 7, the device structure can be realized. simplify.

Further, in the charged particle beam therapy system 1, it is possible to suppress the variation in the delay time until the scanning electromagnet 6 scans the charged particle beam R after the scanning controller 10 transmits the current command value, and the delay time is substantially constant. The influence of the delay time on the irradiation position of the charged particle beam R is obtained by calculation. Therefore, according to the charged particle beam therapy apparatus 1, since the planned position of the charged particle beam R and the actual measurement position can be accurately compared, it is possible to determine whether or not the charged particle beam R is out of the allowable range and deviate from the planned position, and it is possible to determine accurately. Whether there is an abnormality in the scanning control of the charged particle beam R.

The present invention is not limited to the above embodiments. In the above-described embodiment, the charged particle beam therapy apparatus 1 that irradiates a proton line or a heavy particle (heavy ion) line or the like is described. However, the present invention is also applicable to a particle beam irradiation apparatus that irradiates other particle beams.

Further, the configuration may be such that the transmitting unit that transmits the operation timing signal is separately provided to the scanning controller and the scanner power supply, and both the scanning controller and the scanner power supply have a receiving unit.

[Industrial availability]

The present invention can be utilized in a particle beam irradiation apparatus capable of performing scanning control of high-precision particle beams.

1‧‧‧Electrical particle beam therapy device (particle beam irradiation device)

2‧‧‧Accelerator

3‧‧‧ transmission line

4‧‧‧ Department of Irradiation

5‧‧‧Location measurement monitor (location measurement method)

6‧‧‧Scan electromagnet (scanning means)

6A‧‧‧1st scanning electromagnet

6B‧‧‧2nd scanning electromagnet

7‧‧‧Scanner power supply (current supply means)

7A‧‧‧1st power supply (X power supply)

7B‧‧‧2nd power supply (Y power supply)

8‧‧‧Treatment Planning Department

9‧‧‧Lighting Control Department

10‧‧‧Scan controller (scanning control means)

11‧‧‧ Beam Control Department

50‧‧‧ patients

51‧‧‧Tumor (irradiated body)

100‧‧‧ treatment table

A‧‧‧ Direction

R‧‧‧ charged particle beam

Claims (3)

A particle beam irradiation apparatus that irradiates an object to be irradiated with a particle beam, comprising: a scanning means for scanning the particle beam; a current supply means for supplying a current to the scanning means; and a scanning control means for applying the current The supply means transmits a current command value to control the scanning of the particle beam by the scanning means, and the operation timing period of the scanning control means is equal to the period of the operation timing of the current supply means. The particle beam irradiation apparatus according to claim 1, wherein the scanning control means includes a transmitting unit that transmits an operation timing signal to the current supply means, wherein the current supply means includes a receiving unit, and the receiving The unit receives the operation timing signal transmitted by the transmitting unit. The particle beam irradiation apparatus according to claim 1 or 2, further comprising: a position measuring means for measuring a position of the particle beam scanned by the scanning means, the scanning The control means determines whether or not there is an abnormality in the scanning of the particle beam based on a comparison result between the planned position of the particle beam and the measurement position of the particle beam, wherein the planned position of the particle beam corresponds to the current command value, and the particle beam Measuring position by the aforementioned position The measurement means was measured.